1. Field of the Invention
The present invention relates to an ink jet printer and its control method, particularly to an ink jet printer and its control method in which when one dot is recorded with a plurality of colors of ink overlapping, ink blur is prevented from being generated in a recording sheet.
2. Description of the Related Art
In general, an ink jet printer is used as an output device of a computer, a word processor, or the like.
In a conventional ink jet printer, a carriage shaft is disposed in a direction parallel with a platen, and a reciprocatable carriage is disposed along the carriage shaft. Moreover, an ink jet recording head is mounted on the carriage to oppose the platen in such a manner that a head nozzle of the ink jet faces a printing face of the platen.
According to the above conventional ink jet printer, a recording sheet is conveyed between the platen and the ink jet head. While the carriage having the ink jet head mounted thereon moves along the platen, the nozzle of the ink jet head is operated on the basis of a predetermined printing signal, so that the desired ink is ejected or discharged from the nozzle toward the recording sheet on the platen. Thus, a desired image is recorded or printed on the recording sheet.
In such conventional ink jet printer, for example, yellow, magenta, cyan and black inks are used to perform full-color recording. In this case, when the yellow, magenta, cyan and black inks are all ejected from the respective nozzles to record a certain dot, the amount of ink ejected for one dot becomes remarkably large as a result. This causes a problem that the recorded dot blurs and becomes hazy or indistinct, resulting in the deterioration of the recording quality.